Skating has been a well known and popular form of recreation for a long time. Traditionally, it was a seasonal activity performed with a blade carrying skate on ice in winter and with a wheeled skate on smooth paved surfaces in warm weather, but rink facilities creating artificial conditions enabled people to ice skate in warm weather and roller skate in winter. Separate bladed or wheeled skates were still required.
The next development was a shoe or boot adaptable to carry interchangeably a blade or plurality of wheels or rollers. Such skates are represented by the skate or skate devices disclosed in U.S. Pat. Nos. 3,351,353 (Weitzner) and 4,666,169 (Hamill et al.). The Hamill et al. skate apparatus requires a bifurcated truck assembly which must be disconnected from the sole of the shoe and disassembled to switch between wheels and the optional ice skate attachment. The Weitzner patent is directed to a skating shoe with retractable, interchangeable blades, rollers or jump springs. The shoe has a thick sole with a central longitudinal channel having an open rear end and a closed front end. A plate member supporting the springs, rollers or blade is retractably received in the channel and, when retracted, can be covered by a separate plate so that the shoe can be used for walking with a flat sole and heel. There is no disclosure or suggestion in either the Weitzner or Hamill et al. patent about how to provide an interchangeable ski structure for skating on snow.
Two other patents disclosing the concept of interchangeability in skate devices are U.S. Pat. Nos. 4,150,499 (Wang) and 5,127,672 (Horibata). The latter patent discloses a hopping roller skate for the training of skiing wherein the shoe can function in its usual manner when separated from the roller structure. However, the shoe would be unsuitable for substantially normal walking to and from a place of use. While the Wang shoe might be used for normal walking after the blade or rollers are removed, a disadvantage is that it is a sandal type shoe and provides no or very limited support for a user's ankles. Neither Wang or Horibata suggest that a ski could be interchangeably connected to the respective shoes.
U.S. Pat. No. 4,492,385 (Olson) and 4,932,675 (Olson et al.) disclose skates having an interchangeable operative portion, a blade or wheel assembly, fastened to a shoe or boot. Frame members are attached to the sole of the boot and have relieved regions or recesses on each side for receiving beams or edge portions associated with the interchangeable blade or wheel assemblies. There is no disclosure or suggestion in either patent about how a ski could be releasably or interchangeably connected to the shoe or boot.
U.S. Pat. Nos. 4,188,046 (Fleckenstein) and 5,193,839 (Hannes) disclose ski and boot arrangements for snow skating or fancy skiing. The ski disclosed in the former patent includes an integral boot plate and a fairly typical ski binding toe piece and releasable heel binding. The ski is relatively short, being intended for "hot dogging" or trick skiing. The Hannes winter sports equipment is designed for skating and ordinary walking by providing an integral structure formed by a sole plate closely associated with a boot upper. Neither patent discloses or suggests how such a ski and boot arrangement could be adapted for use as a roller skate or ice skate.
It would be advantageous if a convertible sport and training skate could be provided for use in any season, wherein the skate could be adapted to become a roller skate, an ice skate or a snow skate.